temperature = int(input())
if temperature >= 30:
  print('Yes')
else:
  print('No') temperature = int(input()) temperature int(input()) int input() input if temperature >= 30:
  print('Yes')
else:
  print('No') temperature >= 30 temperature 30 print('Yes') print 'Yes' print('No') print 'No' temperature = int(input()) int(input()) temperature
temperature = int(input())
if temperature >= 30:
  print('Yes')
else:
  print('No')